(Quake III crossover fic - not gory, some violence, though)
After beating the first four Tiers of the universe's deadliest tournament, warrior pony Garrison faces his deadliest opponent yet: a mysterious and dangerous pony named Uriel. Will Garrison be able to advance to the next round, or will Uriel claim yet another victim?

Octavia is a successful earth pony cellist who lives in the quiet town of Ponyville, spending most of her time always perfecting her art. But one day, she gets a knock on her door, and realizes she's gotten an unexpected visit from her younger sister, Viviola. They don't always get along - they are siblings, after all - but in the end, they are family.